CNAM (Caller Name Delivery)
Short answer: CNAM (caller ID name) is the name displayed alongside an incoming phone number, mainly in the US and Canada. The name is not sent with the call; the recipient's carrier looks it up in a CNAM database using the calling number and shows up to 15 characters.
Because CNAM is a lookup performed by the receiving carrier, whether and how a name appears depends on that carrier and the database record.
How it works
The owner of a number registers a display name with a CNAM database provider. When a call arrives, the terminating carrier queries a database with the calling number and displays the result, often with a fee per lookup. Outside North America, name display is less common and works differently.
What affects whether a name appears
- The receiving carrier: some perform CNAM lookups by default, some charge the subscriber for the feature, and some do not offer it.
- The database record: if no name is registered for the number, the display may show only the city and state or the number alone.
- Contact lists: a name saved on the phone usually overrides the CNAM result.
- Length and format: CNAM names are limited to 15 characters, so long business names are shortened.
CNAM vs caller ID number vs STIR/SHAKEN
These three terms all describe how an incoming call is identified, but each covers a different piece of information.
| Term | What it carries | Where it comes from |
|---|---|---|
| Caller ID number | The calling phone number | Sent in the call signaling by the originating side |
| CNAM | A display name of up to 15 characters | Looked up by the receiving carrier in a CNAM database |
| STIR/SHAKEN | A signed attestation that the caller may use the number | Added by the originating provider and verified by the receiving one |
Does Smart Messaging offer it?
As stated above, CNAM registration is not listed as part of the Smart Messaging service. What Smart Messaging calls do present is the phone number itself as caller ID, and the web dialer lets you pick which of your numbers is shown on each outgoing call.
How it applies to Smart Messaging
CNAM registration is not listed as part of the Smart Messaging service. Smart Messaging numbers present the phone number itself as caller ID, and in the web dialer you can choose which of your numbers is shown.
Related terms
- Caller ID
- STIR/SHAKEN
- Local number
Frequently asked questions
Is CNAM the same as caller ID?
Caller ID is the number; CNAM is the optional name looked up for that number.
Can I set a CNAM name on a Smart Messaging number?
CNAM is not a listed Smart Messaging feature.
Why does a caller name show incorrectly?
The receiving carrier may use an outdated or different CNAM database.
Does STIR/SHAKEN show the caller name?
No. STIR/SHAKEN verifies whether the caller is authorized to use the number; the name, if any, still comes from a CNAM lookup or branded-calling service.
Is CNAM used outside the US and Canada?
CNAM is mainly a North American system; other countries rarely display network-supplied names, and where they do the method differs.
How long is a CNAM name?
A CNAM display name is limited to 15 characters, including spaces.
Related pages
- caller ID
- STIR/SHAKEN
- local numbers
- US phone number from abroad
- Canada phone number from abroad
- US numbers
- G.711 Codec (PCMU and PCMA)
Sources
- FCC: Caller ID and Spoofing (as of September 2026)
- FCC: Combating Spoofed Robocalls with Caller ID Authentication (as of September 2026)
- Wikipedia: Caller ID (as of September 2026)